Delivery device

ABSTRACT

A delivery device, for example a fan, may include a drive, a rotor, and an impeller connected rotationally conjointly to a rotor hub of the rotor. The impeller may be coupled to the rotor via one or more detent connections. According to an implementation, the rotor may have a pot-shaped structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to German Patent Application No. 10 2015 222 005.2, filed Nov. 9, 2015, the contents of which are hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a delivery device having a drive, which has a rotor, and having an impeller, which is connected rotationally conjointly to a rotor hub of the rotor.

BACKGROUND

U.S. Pat. No. 5,117,656 A has disclosed a generic delivery device in the form of a fan, having a drive, which has a rotor, and having an impeller, which is connected rotationally conjointly to a rotor hub of the rotor.

In general, the installation of delivery devices, such as for example electric fans, is relatively expensive, because use is often made of manual installation methods and/or complex technology involving additional parts. Specifically in the case of electric fans for cooling purposes, it is normally the case that impellers composed of plastic or metal are installed onto an electric drive, which in turn is held in a fan frame. Said fan frame is then installed on the respective heat exchanger. The installation of the impeller on the rotor of the drive has hitherto been performed manually by way of multiple screws. Alternatively, installation methods are also known which utilize hot caulking of two plastics parts, that is to say for example of a rotor hub formed from plastic with an impeller formed from plastic.

A disadvantage of the known installation methods is however that they are relatively expensive, because they can be automated only to a limited extent or not at all, and furthermore require high levels of investment in the production line.

Therefore, the present invention is concerned with the problem of specifying, for a delivery device of the generic type, an improved or at least alternative embodiment by way of which, in particular, the installation of the delivery device can be made simpler and less expensive.

Said problem is solved according to the invention by way of the subject matter of the independent claim(s). The dependent claims relate to advantageous embodiments.

SUMMARY

The present invention is based on the general concept of fixing an impeller of a delivery device, for example of a fan, to a rotor hub of a rotor by way of detent connections, and thus in a relatively simple and fast manner and furthermore without further fastening means. In the case of such detent connections, it is for example possible for the impeller to be simply mounted and locked onto the rotor hub without further fastening means, for example, in particular screws, having to be screwed in manually for this purpose. It would furthermore be possible for the impeller to be pushed onto the rotor hub in this way in automated fashion, whereby there would preferably no longer be any need whatsoever for manual installation. By way of such a detent or clip-type connection, it is possible for both axial forces and torques to be transmitted without problems, wherein uninstallation of an impeller of said type (fan wheel) is also relatively easily possible by way of a simple release of the detent connections. It is furthermore particularly advantageous that the separate fastening means that have hitherto been required, such as for example screws, can be omitted entirely, whereby the variety of parts and furthermore the storage and logistics costs can also be reduced.

The rotor hub is expediently of pot-shaped form, and furthermore, at least three detent hooks which project in an axial direction are arranged on the impeller, which detent hooks engage behind an edge of the rotor hub in the installed state of the impeller. In the case of an impeller formed in this way and an associated rotor hub, the installation of the impeller on the rotor hub is thus realized by way of a simple axial pushing-on movement until the impeller-side detent hooks engage behind the edge of the rotor-side rotor hub and thus fix the impeller on the rotor hub.

In an advantageous refinement of the solution according to the invention, spring elements are provided on the rotor hub or on the impeller, which spring elements brace the impeller against the rotor hub. In this way, it is possible to realize both centering of the impeller with respect to the rotor hub and stabilization of the individual detent connections. To be able to ensure a transmission of torque between the rotor hub and the impeller, it is furthermore possible, for example, for the detent hooks to engage into corresponding recesses on the edge of the rotor hub and to thereby fix the impeller rotationally conjointly to the rotor hub. As an alternative to this, it is self-evidently also possible for the edge to be of continuous form, that is to say without recesses, and for pins to be provided on the impeller and/or on the rotor hub for the purposes of transmitting torque, which pins then engage into corresponding openings arranged on the impeller or on the rotor hub and prevent a relative rotation of the impeller with respect to the rotor hub.

In an advantageous refinement of the solution according to the invention, the impeller and at least the detent hooks are formed as a unipartite plastics injection-moulded part. In particular in the case of a delivery device in the form of a fan, it is expedient for the impeller to be formed as an inexpensive plastics injection-moulded part, wherein, in this context, it is additionally the case that at least the detent hooks, but preferably additionally also the spring elements or for example the pins, can be formed integrally on the impeller and can thereby be produced in a common plastics injection moulding process. In this way, the impeller can be produced relatively inexpensively and nevertheless with high quality. In the same way, it is self-evidently also possible for the rotor hub to be formed as a plastics injection-moulded part.

In an alternative embodiment of the delivery device according to the invention, the rotor hub is likewise of pot-shaped form and has at least three first and at least three second openings. In this case, at least three hook elements and at least three clip elements, which are subjected to pressure load, are arranged on the impeller, wherein the at least three hook elements engage behind an edge of an associated first opening in the installed state, and the at least three clip elements engage into the associated second openings and thereby fix the impeller rotationally conjointly, and axially without play owing to the preload, to the rotor hub. The first and/or the second openings are in this case preferably arranged in a face side of the rotor hub. Purely theoretically, it would self-evidently also be conceivable for the hook and clip elements to be formed on the rotor hub and for the associated first and second openings to be formed on the impeller. With the hook and clip elements, it is likewise the case that relatively simple, fast and furthermore automatable installation of the impeller on the rotor hub is possible, because, for installation purposes, the impeller merely has to be pushed onto the rotor hub and subsequently rotated relative to the rotor hub, in the manner of a bayonet fastening, until the three hook elements engage behind the edge of the associated first openings and the three clip elements have engaged with detent action into the associated second openings.

In an advantageous refinement of the solution according to the invention, the at least three first openings narrow in a circumferential direction. Owing to the wedge-like form of the at least three first openings, it is possible to realize relatively simple installation, in particular a simple insertion of the hook elements into the associated first openings, wherein, owing to the narrowing first openings, radial positioning of the impeller relative to the rotor hub can be realized. Furthermore, with first openings and associated hook elements precisely coordinated with one another, it is generally possible to realize forced radial fixing of the impeller of the rotor hub.

In a further advantageous embodiment of the solution according to the invention, the impeller and at least the hook elements are in the form of a unipartite plastics injection-moulded part. Here, the clip elements may likewise be formed in one piece together with the impeller and the hook elements, or else may be separate metal elements. The unipartite embodiment in particular offers the great advantage here that the impeller can be produced relatively inexpensively but nevertheless with high quality.

The delivery device is expediently in the form of a fan. A fan of said type may be used for example in an air-conditioning system of a motor vehicle, wherein it is self-evidently also possible for other delivery devices, for example pump devices for liquid, to be equipped with the impeller fixed to the rotor hub in accordance with the invention by way of detent connections.

Further important features and advantages of the invention will emerge from the subclaims, from the drawings and from the associated figure description on the basis of the drawings.

It is self-evident that the features mentioned above and the features yet to be discussed below may be used not only in the respectively specified combination but also in other combinations or individually without departing from the scope of the present invention.

Preferred exemplary embodiments of the invention are illustrated in the drawings and will be discussed in more detail in the following description, wherein the same reference designations are used to denote identical or similar or functionally identical components.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, in each case schematically:

FIG. 1 is a partially sectional illustration through an impeller in a state fastened to a rotor hub,

FIG. 2 is a detail illustration from FIG. 1,

FIG. 3 shows an impeller of a delivery device according to the invention in a front view and in a rear view,

FIG. 4 shows a rotor hub of a delivery device according to the invention, again in a front view and in a rear view,

FIG. 5 is an illustration as in the rear view from FIG. 4, but with an impeller installed,

FIG. 6 shows a further possible alternative embodiment of the impeller in a front view,

FIG. 7 is an illustration as in FIG. 6, but in a rear view,

FIG. 8 is an illustration as in FIG. 5, but with the impeller illustrated in FIGS. 6 and 7,

FIG. 9 is a sectional illustration through FIG. 5 in the region of the hook and clip elements in the case of a detent connection not yet having been made,

FIG. 10 is a sectional illustration as in FIG. 9, but with a detent connection having been made.

DETAILED DESCRIPTION

Correspondingly to FIGS. 1, 2 and 5 and 8, a delivery device 1 according to the invention, which may for example be in the form of a fan in a motor vehicle, has a drive 3, which drive has a rotor 2, and an impeller 5, which impeller is connected rotationally conjointly to a rotor hub 4 of the rotor 2. According to the invention, it is now the case that the impeller 5 is coupled, that is to say connected, by way of detent connections 6 to the rotor 2 or to the rotor hub 4 thereof. Here, the detent connections 6 may be configured differently, specifically firstly as per the embodiments illustrated in FIGS. 1 and 2 and secondly as per the embodiments illustrated in FIGS. 3 to 8.

Considering firstly the rotor 2 of the delivery device 1 according to the invention as per FIGS. 1 and 2, it can be seen that the rotor hub 4 is of pot-shaped form and, on the impeller 5, there are arranged at least three detent hooks 8 which project in an axial direction 7 and which, when the impeller 5 is in an installed state, engage behind an edge 9 of the rotor hub 4. In this way, relatively simple installation of the impeller 5 on the rotor hub 4 of the rotor 2 of the delivery device 1 is possible by way of simple axial mounting of the impeller 5 onto the rotor hub 4. In particular, in this way, hitherto required separate fastening elements, such as for example screws, can be omitted, whereby not only is the mounting process simplified but also the variety of parts, and in association therewith the storage and logistics costs, can be reduced.

Furthermore, on the rotor hub 4 or on the impeller 5, there are provided spring elements 10 which brace the impeller 5 against the rotor hub 4. The spring elements 10 are in this case supported on a shell surface of the rotor hub 4. Here, the spring elements 10 have a shorter spring travel than the snap-action hooks 8. Here, the spring elements 10 may self-evidently also have an insertion bevel which facilitates the installation.

To be able to produce the impeller 5 both with high quality and inexpensively, it is the case that at least the impeller 5 and the detent hooks 8 are in the form of a unipartite plastics injection-moulded part. In the present case, it is self-evidently also the case that the spring elements 10 are formed in one piece with the impeller 5, wherein the embodiment of the spring elements 10 illustrated in FIG. 2 constitutes merely one possible embodiment, such that spring elements 10 of said type may also be formed in some other way. The detent hooks 8 are in this case structurally preloaded in a radially inward direction and thereby reliably hold the impeller 5 fixed on the wheel hub 4 when the detent connections 6 have been made. The axial length of the individual detent hooks 8 is in this case dimensioned such that the detent connections 6 can be made, that is to say the detent hooks 8 engage behind the edge 9 of the wheel hub 4, only if the impeller 5 has been pushed on in the correct position.

Furthermore, on the impeller 5, there may also be arranged pins 11 which are formed in one piece with said impeller and which engage into associated recesses 12 on the wheel hub 4 and thereby connect the impeller 5 rotationally conjointly to the wheel hub 4. Similarly, it would self-evidently also be possible for corresponding recesses to be provided on the edge 9 in the region of the respective detent hooks 8.

Considering a second alternative embodiment of the delivery device 1 according to the invention, as illustrated in FIGS. 3 to 10, it can be seen in said embodiment that the rotor hub 4 is of pot-shaped form and has at least three first openings 13 and at least three second openings 14. At least three hook elements 15 and at least three clip elements 16 are arranged on the impeller 5, wherein the at least three hook elements 15 engage behind an edge 17 (cf. FIGS. 5 and 8-10) of an associated first opening 13 in the installed state, whereas the at least three clip elements 16 engage into the associated second openings 14 and thereby fix the impeller 5 rotationally conjointly to the rotor hub 4. The clip elements 16 may in this case be in the form of individual spring tongues, as illustrated in FIGS. 3 and 5, 9 and 10, or dual spring tongues, as illustrated in FIGS. 6 to 8.

The at least three hook elements 15 are oriented in a circumferential direction, wherein the at least three clip elements 16 in the form of single spring tongues are oriented oppositely with respect thereto (cf. FIG. 5). This offers the major advantage that installation of the impeller 5 on the wheel hub 4 is possible relatively easily by virtue of the impeller 5 firstly being mounted onto the wheel hub 4 in an axial direction (cf. FIG. 9) and subsequently being rotated relative to said wheel hub until the hook elements 15 engage behind the edge 17 of the respectively associated first opening 13 (cf. FIG. 10). In the event of a further relative rotation, the clip elements 16 engage into the associated second openings 14 and, in so doing, owing to their orientation opposite to the hook elements 15, generate a rotationally fixed connection between the impeller 5, on the one hand, and the wheel hub 4, on the other hand. In the same way, this is also effected by way of the clip elements 16 with two spring tongues (cf. FIGS. 6 to 8), the orientation of which is however directed not in the circumferential direction but in the radial direction.

It is preferably also the case in the delivery device 1 as per FIGS. 3 to 10 that the impeller 5 and at least the hook elements 15, preferably self-evidently also additionally the clip elements 16, are in the form of a unipartite plastics injection-moulded part, whereby it is possible for the impeller 5 to be manufactured inexpensively and at the same time with high quality. In all cases, it is additionally also possible for the rotor hub 4 to be in the form of a plastics injection-moulded part. The hook elements 15 or clip elements 16 arranged on the impeller 5 could self-evidently also be arranged on the wheel hub 4 in a reversed manner, wherein, in this case, the associated first and second openings 13, 14 would then be arranged on the impeller 5.

In all embodiments, it is self-evidently additionally possible for screw engagement openings 18 to be provided in the impeller 5, which screw engagement openings are, in the installed state, aligned with an internal thread 19 arranged on the wheel hub 4 and which screw engagement openings permit an additional fixing of the impeller 5 to the wheel hub 4 by way of separate fastening means, for example screws.

With the delivery device 1 according to the invention, it is possible in particular for installation time and thus also installation costs to be reduced, because, in particular, the screwing process hitherto required can be omitted. Furthermore, with the detent connections 6 according to the invention it is possible to realize a simultaneously easily connectable and easily releasable fixing of the impeller 5 to the wheel hub 4, wherein the manufacturing process that has hitherto been performed exclusively manually is now even automatable. 

1. A delivery device comprising: a drive, a rotor, and an impeller connected rotationally conjointly to a rotor hub of the rotor, wherein the impeller is coupled to the rotor via a detent connection.
 2. The delivery device according to claim 1, wherein the rotor hub has a pot-shaped structure, and further including at least three detent hooks arranged on the impeller and projecting in an axial direction, wherein the at least three detent hooks engage behind an edge of the rotor hub when the impeller is installed.
 3. The delivery device according to claim 1, further comprising a spring element provided on at least one of the rotor hub and the impeller, wherein the spring element braces the impeller against the rotor hub.
 4. The delivery device according to claim 2, wherein the impeller and at least the at least three detent hooks are structured as a unipartite plastics injection-moulded part.
 5. The delivery device according to claim 1, wherein the rotor hub has a pot-shaped structure and includes at least three first openings and at least three second openings; and further including at least three hook elements and at least three clip elements arranged on the impeller, wherein the at least three hook elements engage behind an edge of an associated one of the at least three first openings when the impeller is installed, and the at least three clip elements engage into an associated one of the at least three second openings and fix the impeller rotationally conjointly to the rotor hub.
 6. The delivery device according to claim 5, wherein the at least three hook elements are oriented in a circumferential direction.
 7. The delivery device according to claim 5, wherein the at least three first openings narrow in a circumferential direction.
 8. The delivery device according to claim 5, wherein the at least three hook elements and the at least three clip elements are oriented oppositely to one another.
 9. The delivery device according to claim 5, wherein the impeller and at least the at least three hook elements are structured as a unipartite plastics injection-moulded part.
 10. The delivery device according to claim 1, wherein at least one of: the rotor hub is a plastics injection-moulded part, and the delivery device is configured as a fan.
 11. The delivery device according to claim 1, further comprising a plurality of axially projecting detent hooks arranged on the impeller, wherein the plurality of axially projecting detent hooks engage behind an edge of the rotor hub when the impeller is installed.
 12. The delivery device according to claim 1, wherein the rotor hub includes a plurality of first openings and a plurality of second openings; and further including a plurality of hook elements and a plurality of clip elements arranged on the impeller; wherein the plurality of hook elements engage behind an edge of a corresponding one of the plurality of first openings and the plurality of clip elements engage into a corresponding one of the plurality of second openings when the impeller is installed.
 13. The delivery device according to claim 12, wherein at least one of the plurality of hook elements is oriented oppositely to at least one of the plurality of clip elements.
 14. The delivery device according to claim 2, further comprising a spring element arranged to brace the impeller against the rotor hub.
 15. The delivery device according to claim 14, wherein the impeller and the at least three detent hooks are structured as a unipartite plastics injection-moulded part.
 16. The delivery device according to claim 5, wherein the rotor hub is structured as a plastics injection-moulded part.
 17. The delivery device according to claim 6, wherein the at least three hook elements and the at least three clip elements are oriented oppositely to one another.
 18. A delivery device, comprising: a drive; a rotor including a rotor hub; and an impeller connected rotationally conjointly to the rotor hub of the rotor; wherein the impeller is coupled to the rotor at a detent connection including at least one detent mechanism.
 19. The delivery device according to claim 18, wherein the at least one detent mechanism includes a plurality of detent hooks arranged on the impeller and projecting in an axial direction of the rotor, and wherein the plurality of detent hooks engage behind an edge of the rotor hub when the impeller is installed.
 20. The delivery device according to claim 18, wherein the at least one detent mechanism includes a plurality of hook elements and a plurality of clip elements arranged on the impeller; wherein the rotor hub includes a plurality of first openings and a plurality of second openings; and wherein the plurality of hook elements engage behind an edge of a corresponding one of the plurality of first openings and the plurality of clip elements engage into a corresponding one of the plurality of second openings when the impeller is coupled to the rotor. 